1. Field of the Invention
The present invention relates to elastic blocks made of elastic materials which are to be used as pavement materials for underlining bases such as road bases and floor bases in pavements, promenades, bicycle roads, outdoor sport facilities, indoor sport facilities, squares and plazas, rooftops, club houses in golf courses, halls, passenger boats, public facilities, parks, schools, etc., and which are suitable for enhancing safety in cases where persons, particularly aged persons, infants and children fall.
2. Related Art Statement
The elastic pavement roads constituted by such elastic blocks have been frequently used in pavements, promenades, gymnastic facilities, jogging roads, pavements in golf courses.
As compared with interlocking blocks made of inorganic materials such as concrete, resinous mortar or tiles, the elastic blocks of the present invention are made of organic elastic pavement materials that are softer and, therefore, safer than the inorganic materials used in known interlocking blocks.
As the organic elastic pavement material, a water non-permeable elastic pavement material formed by spreading a polyurethane-based resin with a trowel or the like is known.
Further, water-permeable elastic blocks in which rubber chips obtained by grinding tires or the like are bound to one another with a synthetic resin binder such as a urethane resin are known.
FIG. 7 shows a sectional view of such a block. This block 61 includes a front-surface layer 64 and a rear-surface layer 65 in which rubber chips 66 and 67, obtained by grinding tires or the like, having respectively different dimensions are bound together using a synthetic resin binder, such as urethane resin, so that the resulting block exhibits excellent water permeability.
When a paved road is to be constructed by using such elastic blocks, the road is first paved with asphalt or concrete, the asphalt or the concrete is cured, and then a number of elastic blocks are paved on the cured layer, and entirely joined thereto with an adhesive, thereby forming the paved road.
The elastically paved road constructed by spreading the poly-urethane-based resin with the trowels has no water permeability. Such a paved road repels water, so that it causes pedestrians to slip or fall with staying water on walking, if the road has poor drainage.
On the other hand, the elastic blocks in which rubber chips obtained by grinding tires or the like are fixedly bound to one another with a synthetic resin binder such as a urethane resin have water permeability, so that they prevent water from staying at their surfaces. As a result, they have high safety and can enhance walk feeling, so that they are frequently used.
However, the present inventors found out that if such elastic blocks are used for a long time, their upper layer portions warped.
The upwardly warped blocks as a matter of course deteriorate the appearance of the paved road, and form steps at the warped portions, which cause pedestrians to stumble and fall and become safety problems.
The present invention is aimed at obtaining elastic blocks which can are prevented from being upwardly warped and have excellent safety and constructionability.
The present invention relates to an elastic block adapted to be paved on an underlying base for absorbing impacts, said elastic body comprising a laminate composed of a powdery rubber-containing layer and a vulcanized rubber layer underlying the powdery rubber-containing layer, said powdery rubber-containing layer being a compression molded layer composed of a mixture comprising elastic chips having the particle size of 0.5 to 10 mm and a resin binder, said vulcanized rubber layer being a vulcanized molding of an unvulcanized rubber layer, wherein the elastic chips are fixedly bonded to one another with the resin binder and the powdery rubber-containing layer is adhered to the vulcanized rubber layer when the mixture layer and the unvulcanized rubber layer are subjected to pressurization and vulcanization. The invention also relates to a process for producing the same.
The present invention clarified the causes warping the upper layer portions of the elastic blocks when used for a long time, and overcomes the warping problems of the elastic blocks by removing those causes.
The above and other objects, features and advantages of the invention will be appreciated upon reading of the following description of the invention when taken in conjunction with the attached drawings, with the understanding that some modifications, variations and changes of the invention could be easily made by the skilled person in the art.